ID   K118B_XENLA             Reviewed;         432 AA.
AC   Q7SY65;
DT   29-MAY-2007, integrated into UniProtKB/Swiss-Prot.
DT   01-OCT-2003, sequence version 1.
DT   03-AUG-2022, entry version 74.
DE   RecName: Full=Keratin, type I cytoskeletal 18-B;
DE   AltName: Full=Cytokeratin-18-B;
DE            Short=CK-18-B;
DE   AltName: Full=Keratin-18-B;
DE            Short=K18-B;
GN   Name=krt18-b;
OS   Xenopus laevis (African clawed frog).
OC   Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Amphibia;
OC   Batrachia; Anura; Pipoidea; Pipidae; Xenopodinae; Xenopus; Xenopus.
OX   NCBI_TaxID=8355;
RN   [1] {ECO:0000305, ECO:0000312|EMBL:AAH54993.1}
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA].
RC   TISSUE=Tadpole {ECO:0000312|EMBL:AAH54993.1};
RG   NIH - Xenopus Gene Collection (XGC) project;
RL   Submitted (JUL-2003) to the EMBL/GenBank/DDBJ databases.
CC   -!- FUNCTION: When phosphorylated, plays a role in filament reorganization.
CC       {ECO:0000250}.
CC   -!- SUBUNIT: Heterotetramer of two type I and two type II keratins.
CC       Keratin-18 associates with keratin-8 (By similarity). {ECO:0000250}.
CC   -!- PTM: Phosphorylated. {ECO:0000250}.
CC   -!- PTM: Proteolytically cleaved by caspases during epithelial cell
CC       apoptosis. {ECO:0000250}.
CC   -!- MISCELLANEOUS: There are two types of cytoskeletal and microfibrillar
CC       keratin: I (acidic; 40-55 kDa) and II (neutral to basic; 56-70 kDa).
CC       {ECO:0000305}.
CC   -!- SIMILARITY: Belongs to the intermediate filament family.
CC       {ECO:0000255|PROSITE-ProRule:PRU01188}.
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DR   EMBL; BC054993; AAH54993.1; -; mRNA.
DR   RefSeq; NP_001080810.1; NM_001087341.1.
DR   AlphaFoldDB; Q7SY65; -.
DR   SMR; Q7SY65; -.
DR   BioGRID; 98746; 2.
DR   IntAct; Q7SY65; 1.
DR   PRIDE; Q7SY65; -.
DR   DNASU; 380504; -.
DR   GeneID; 380504; -.
DR   KEGG; xla:380504; -.
DR   CTD; 380504; -.
DR   Xenbase; XB-GENE-6256523; krt18.1.L.
DR   OrthoDB; 711591at2759; -.
DR   Proteomes; UP000186698; Chromosome 2L.
DR   Bgee; 380504; Expressed in neurula embryo and 19 other tissues.
DR   GO; GO:0005882; C:intermediate filament; IEA:UniProtKB-KW.
DR   GO; GO:0005198; F:structural molecule activity; IEA:InterPro.
DR   InterPro; IPR018039; IF_conserved.
DR   InterPro; IPR039008; IF_rod_dom.
DR   InterPro; IPR027695; Keratin-18.
DR   InterPro; IPR002957; Keratin_I.
DR   PANTHER; PTHR23239; PTHR23239; 1.
DR   PANTHER; PTHR23239:SF349; PTHR23239:SF349; 1.
DR   Pfam; PF00038; Filament; 1.
DR   PRINTS; PR01248; TYPE1KERATIN.
DR   SMART; SM01391; Filament; 1.
DR   PROSITE; PS00226; IF_ROD_1; 1.
DR   PROSITE; PS51842; IF_ROD_2; 1.
PE   2: Evidence at transcript level;
KW   Coiled coil; Intermediate filament; Keratin; Phosphoprotein;
KW   Reference proteome.
FT   INIT_MET        1
FT                   /note="Removed"
FT                   /evidence="ECO:0000250|UniProtKB:P05783"
FT   CHAIN           2..432
FT                   /note="Keratin, type I cytoskeletal 18-B"
FT                   /id="PRO_0000289077"
FT   DOMAIN          83..393
FT                   /note="IF rod"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU01188"
FT   REGION          1..44
FT                   /note="Disordered"
FT                   /evidence="ECO:0000256|SAM:MobiDB-lite"
FT   REGION          2..82
FT                   /note="Head"
FT                   /evidence="ECO:0000255"
FT   REGION          83..118
FT                   /note="Coil 1A"
FT                   /evidence="ECO:0000255"
FT   REGION          119..134
FT                   /note="Linker 1"
FT                   /evidence="ECO:0000255"
FT   REGION          135..226
FT                   /note="Coil 1B"
FT                   /evidence="ECO:0000255"
FT   REGION          227..250
FT                   /note="Linker 12"
FT                   /evidence="ECO:0000255"
FT   REGION          251..388
FT                   /note="Coil 2"
FT                   /evidence="ECO:0000255"
FT   REGION          389..432
FT                   /note="Tail"
FT                   /evidence="ECO:0000255"
FT   COMPBIAS        1..19
FT                   /note="Polar residues"
FT                   /evidence="ECO:0000256|SAM:MobiDB-lite"
FT   SITE            240..241
FT                   /note="Cleavage; by caspases"
FT                   /evidence="ECO:0000250"
FT   SITE            333
FT                   /note="Stutter"
FT                   /evidence="ECO:0000255"
SQ   SEQUENCE   432 AA;  48004 MW;  E86213DA05CC4213 CRC64;
     MSYSRSMYSS SSVVGGSPYR SLSSAPRFAP GSSAASVHAG PGGSGARISV SRVSSVGSGF
     GGGFSGGFSG VSNVSLMGGA QNEKETMQDL NDRLASYLER VRSLETANKE LEVQIRQHTE
     KKGPAKDWSP YYKAIEDLKK QVFDSTVDNS QLVLQIDNAR LAADDFRVKY EAELAIRMSV
     ETDIGGLRKL IDDTNISRLN LENEIESLKE ELIFLKKNHQ DDVNELQAQI ARSAVTVEVD
     APKSQDLGKI MAELRAQYDG LAQKNREDVE KWYQSKVEEH TMQVNIDTQE LQTSKNSVTE
     LRRTMQSLEI ELESLRNQKA SLEGTLHDTE ARYAMELEML GGTAMARESE LVQVRSDCQR
     QQQEYQALLN TKMKLEAEIH TYRRLLEGDS FDLQDAVPTV TTQTVKKVIT TTQRIVDGKV
     VAESNDTEVL KA